A device characterization measurement system is one that measures certain parameters of a Device Under Test (DUT) by sampling and measuring signals applied to and coming from the DUT.
Such a system may use various instruments, such as signal generators, spectrum analyzers, power meters, network analyzers in order to characterize the DUT.
A “tuner system”, “automated tuner system”, “impedance tuner system” or “load pull system” refers to a device characterization measurement system which uses some form of impedance tuner(s) to control the impedance(s) seen by the DUT, and measure certain parameters as a function of varying impedance.
Impedance tuners may be mechanical and utilize mismatch probes, or solid-state and utilize switches or diodes. As used herein, “probes” will refer to mismatch probes.
The specific position of mismatch probe, or the state of the switch or diode, will dictate the impedance presented to the DUT.
Impedance tuners may be “manual tuners” where the impedance tuner is manually controlled by the user without influence of a computer, or “automated tuners” which are controlled by a computer or microprocessor.
Automated impedance tuners use some form of software, either embedded within the tuner or standalone on an external computer, to control the probe position or impedance state.
External software, i.e. software installed not within the tuner's memory but on a separate and distinct computer system, is used to characterize a tuner which associates scattering parameters (s-parameters) with tuner positions or states.
External software is used to perform calibration and measurements, which includes communicating with various instruments in the tuner system, reading data from said instruments and de-embedding results to the DUT reference plane.